After reading multiple threads on the appliance pro site, I determined that the problem was most likely the temperature control, however since I had to empty the entire unit and remove the back panel to replace it, I decided to go ahead and replace the defrost thermostat as well. I figured for $50 total, what the heck. So not exactly sure which replacement part solved the problem but the unit is back up and running again and saved my self probably $400 on a new unit.
I will say, that Appliance Pros had very fast shipping and the site was easy to use to find the solution and the parts to fix it. Very pleased.